Expand README with the Rust bits

Author: davidsteiner

README.md

@@ -1 +1,22 @@
 # Serverless Rust API Demo
+
+This is the accompanying repository for the
+"Serverless Rust API on AWS" blog post series.
+
+It contains the code for running a Poem-based web API
+on AWS Lambda. Deployments are done using AWS CDK.
+
+## Pre-requisites
+
+- A recent version of Rust
+
+## To run the application locally
+
+In order to run the application locally, run
+
+```shell
+cargo run --bin local
+```
+
+You can use Swagger UI to view the API documentation
+at http://0.0.0.0:3000.

src/api.rs

@@ -26,7 +26,7 @@ mod tests {
     use poem::Endpoint;
     use std::sync::Arc;
 
-    use crate::build_app;
+    use crate::api::build_app;
     use crate::repository::{Currency, InMemoryRepository};
 
     fn setup_client() -> TestClient<impl Endpoint> {